I was just playing around with three high-end noise gates (Aphex 622 and two
dbx 172's). One thing I noticed with ALL three of these units... when the
bypass switch was pressed, the apparent volume of the signal would become
lower... when the processor was switched in, the signal would become louder.
(This is of course with the gate threshold set so that the gate function
itself would not come into play). It appears that both brand gate units are
either amplifying the signal when the processor is inline, or they are
attenuating the signal when in "bypass" mode. It appears that both these
units have hard-wire bypasses. (Note: I also made sure that the expander
functions were not effecting the volume of the signals). So, what's the
deal, technically speaking? If the signals are being amplified in these
gate units, then it makes me question how pure the signal will be after
being fed through a typical high-quality gate unit. Of course it is best to
run any given signal through as little processing as possible when in doubt,
but I do often find gates to be helpful... but at the same time, I'd hate to
run some very important tracks through a unit that might "degrade" the
quality of the signal in some way. It is hard to do a true "A/B" comparison
test between the processed signal and bypassed signal with these gates being
that the volume is different in each mode. Guess I'd need to record the
signals and then match the volume of each in order to make a comparison.
The processed signal does not initially strike me as being tainted in any
way, but sometimes subtle degradations are hard to pick out unless you are
able to do a side by side comparison. Can anyone comment on the above? Are
gate units (even high-end ones) known to degrade the signal? Do they indeed
amplify the signal? Are some gates better than others in terms of
preserving signal purity? (In terms of gate operation and build-quality,
the dbx 172 and Aphex 622 seem to be by far the best I've ever used...
Drawmers and some older Valley units are not as heavy-duty nor seem to have
the quality of the Aphex and dbx... are there any other really good gates
out there?)